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Make a unique navigation solution with L80 and STM32F746ZG

Easily chart your course with utmost simplicity

GPS3 Click with UNI-DS v8

Published Jun 21, 2023

Click board™

GPS3 Click

Development board

UNI-DS v8

Compiler

NECTO Studio

MCU

STM32F746ZG

Unleash the boundless potential of navigation technology, revolutionizing the way people explore and navigate

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Hardware Overview

How does it work?

GPS3 Click is based on the L80, a GPS receiver module with a patch antenna equipped with an MTK positioning engine from Quectel. With an embedded LNA at a nominal frequency of 1575.42MHz, the L80 receives an L1 band signal from the GPS satellites. This module uses 66 search channels and 22 simultaneous tracking channels, making it possible to track and find satellites within the shortest time, even when the signal is in a signal-challenging environment. The embedded flash memory stores useful navigation data and performs updates. The L80 communicates with the host MUC using the UART interface with commonly used UART RX and TX

pins as its communication protocol operating at 9600bps. In addition, there is an RST pin for resetting the device. The GPS 3 Click also features a VBAT connector for connecting a battery for the RTC domain, which helps lower the power consumption. Regarding battery usage, the VCC-BCKP solder jumper should be removed. While the current date and time are transmitted in NMEA sentences (UTC), a precise and accurate timing signal is provided and indicated using a red LED indicator marked as PPS. The GPS 3 Click also features the u.FL connector for connecting the appropriate active antenna offered by MIKROE for improved range and received signal strength.

The antenna detection and switching functions will handle the connecting source without a hassle while keeping positioning. The detection result, notification, and statuses of the antennas will also be included in the NMEA message. This Click board™ can only be operated from a 3.3V logic voltage level. Therefore, the board must perform appropriate logic voltage conversion before using MCUs with different logic levels. However, the Click board™ comes equipped with a library containing functions and an example code that can be used as a reference for further development.

GPS3 Click hardware overview image

Features overview

Development board

UNI-DS v8 is a development board specially designed for the needs of rapid development of embedded applications. It supports a wide range of microcontrollers, such as different STM32, Kinetis, TIVA, CEC, MSP, PIC, dsPIC, PIC32, and AVR MCUs regardless of their number of pins, and a broad set of unique functions, such as the first-ever embedded debugger/programmer over WiFi. The development board is well organized and designed so that the end-user has all the necessary elements, such as switches, buttons, indicators, connectors, and others, in one place. Thanks to innovative manufacturing technology, UNI-DS v8 provides a fluid and immersive working experience, allowing access anywhere and under any

circumstances at any time. Each part of the UNI-DS v8 development board contains the components necessary for the most efficient operation of the same board. An advanced integrated CODEGRIP programmer/debugger module offers many valuable programming/debugging options, including support for JTAG, SWD, and SWO Trace (Single Wire Output)), and seamless integration with the Mikroe software environment. Besides, it also includes a clean and regulated power supply module for the development board. It can use a wide range of external power sources, including a battery, an external 12V power supply, and a power source via the USB Type-C (USB-C) connector. Communication options such as USB-UART, USB

HOST/DEVICE, CAN (on the MCU card, if supported), and Ethernet is also included. In addition, it also has the well-established mikroBUS™ standard, a standardized socket for the MCU card (SiBRAIN standard), and two display options for the TFT board line of products and character-based LCD. UNI-DS v8 is an integral part of the Mikroe ecosystem for rapid development. Natively supported by Mikroe software tools, it covers many aspects of prototyping and development thanks to a considerable number of different Click boards™ (over a thousand boards), the number of which is growing every day.

UNI-DS v8 horizontal image

Microcontroller Overview

MCU Card / MCU

default

Type

8th Generation

Architecture

ARM Cortex-M7

MCU Memory (KB)

1024

Silicon Vendor

STMicroelectronics

Pin count

144

RAM (Bytes)

327680

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
Reset
PE11
RST
NC
NC
CS
NC
NC
SCK
NC
NC
MISO
NC
NC
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
NC
NC
PWM
NC
NC
INT
UART TX
PB6
TX
UART RX
PB7
RX
NC
NC
SCL
NC
NC
SDA
NC
NC
5V
Ground
GND
GND
1

Take a closer look

Schematic

GPS3 Click Schematic schematic

Step by step

Project assembly

Fusion for PIC v8 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the UNI-DS v8 as your development board.

Fusion for PIC v8 front image hardware assembly
Buck 22 Click front image hardware assembly
SiBRAIN for PIC32MZ1024EFK144 front image hardware assembly
v8 SiBRAIN MB 1 - upright/background hardware assembly
Necto image step 2 hardware assembly
Necto image step 3 hardware assembly
Necto image step 4 hardware assembly
NECTO Compiler Selection Step Image hardware assembly
NECTO Output Selection Step Image hardware assembly
Necto image step 6 hardware assembly
Necto image step 7 hardware assembly
Necto image step 8 hardware assembly
Necto image step 9 hardware assembly
Necto image step 10 hardware assembly
Necto PreFlash Image hardware assembly

Track your results in real time

Application Output

After pressing the "FLASH" button on the left-side panel, it is necessary to open the UART terminal to display the achieved results. By clicking on the Tools icon in the right-hand panel, multiple different functions are displayed, among which is the UART Terminal. Click on the offered "UART Terminal" icon.

UART Application Output Step 1

Once the UART terminal is opened, the window takes on a new form. At the top of the tab are two buttons, one for adjusting the parameters of the UART terminal and the other for connecting the UART terminal. The tab's lower part is reserved for displaying the achieved results. Before connecting, the terminal has a Disconnected status, indicating that the terminal is not yet active. Before connecting, it is necessary to check the set parameters of the UART terminal. Click on the "OPTIONS" button.

UART Application Output Step 2

In the newly opened UART Terminal Options field, we check if the terminal settings are correct, such as the set port and the Baud rate of UART communication. If the data is not displayed properly, it is possible that the Baud rate value is not set correctly and needs to be adjusted to 115200. If all the parameters are set correctly, click on "CONFIGURE".

UART Application Output Step 3

The next step is to click on the "CONNECT" button, after which the terminal status changes from Disconnected to Connected in green, and the data is displayed in the Received data field.

UART Application Output Step 4

Software Support

Library Description

This library contains API for GPS3 Click driver.

Key functions:

  • gps3_generic_read - This function reads a desired number of data bytes by using UART serial interface

  • gps3_clear_ring_buffers - This function clears UART TX and RX ring buffers

  • gps3_parse_gpgga - This function parses the GPGGA data from the read response buffer

Open Source

Code example

This example can be found in NECTO Studio. Feel free to download the code, or you can copy the code below.

/*!
 * @file main.c
 * @brief GPS 3 Click Example.
 *
 * # Description
 * This example demonstrates the use of GPS 3 click by reading and displaying
 * the GPS coordinates.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializes the driver and logger.
 *
 * ## Application Task
 * Reads the received data, parses the GPGGA info from it, and once it receives the position fix
 * it will start displaying the coordinates on the USB UART.
 *
 * ## Additional Function
 * - static void gps3_clear_app_buf ( void )
 * - static err_t gps3_process ( gps3_t *ctx )
 * - static void gps3_parser_application ( char *rsp )
 * 
 * @author Stefan Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "gps3.h"
#include "string.h"

#define PROCESS_BUFFER_SIZE 200

static gps3_t gps3;
static log_t logger;

static char app_buf[ PROCESS_BUFFER_SIZE ] = { 0 };
static int32_t app_buf_len = 0;

/**
 * @brief GPS 3 clearing application buffer.
 * @details This function clears memory of application buffer and reset its length.
 * @return None.
 * @note None.
 */
static void gps3_clear_app_buf ( void );

/**
 * @brief GPS 3 data reading function.
 * @details This function reads data from device and concatenates data to application buffer.
 * @param[in] ctx : Click context object.
 * See #gps3_t object definition for detailed explanation.
 * @return @li @c  0 - Read some data.
 *         @li @c -1 - Nothing is read.
 * See #err_t definition for detailed explanation.
 * @note None.
 */
static err_t gps3_process ( gps3_t *ctx );

/**
 * @brief GPS 3 parser application function.
 * @details This function parses GNSS data and logs it on the USB UART. It clears app and ring buffers
 * after successfully parsing data.
 * @param[in] ctx : Click context object.
 * See #gps3_t object definition for detailed explanation.
 * @param[in] rsp Response buffer.
 * @return None.
 * @note None.
 */
static void gps3_parser_application ( gps3_t *ctx, char *rsp );

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    gps3_cfg_t gps3_cfg;  /**< Click config object. */

    /** 
     * Logger initialization.
     * Default baud rate: 115200
     * Default log level: LOG_LEVEL_DEBUG
     * @note If USB_UART_RX and USB_UART_TX 
     * are defined as HAL_PIN_NC, you will 
     * need to define them manually for log to work. 
     * See @b LOG_MAP_USB_UART macro definition for detailed explanation.
     */
    LOG_MAP_USB_UART( log_cfg );
    log_init( &logger, &log_cfg );
    log_info( &logger, " Application Init " );

    // Click initialization.
    gps3_cfg_setup( &gps3_cfg );
    GPS3_MAP_MIKROBUS( gps3_cfg, MIKROBUS_1 );
    if ( UART_ERROR == gps3_init( &gps3, &gps3_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    log_info( &logger, " Application Task " );
}

void application_task ( void ) 
{
    if ( GPS3_OK == gps3_process( &gps3 ) )
    {
        if ( PROCESS_BUFFER_SIZE == app_buf_len )
        {
            gps3_parser_application( &gps3, app_buf );
        }
    }
}

void main ( void ) 
{
    application_init( );

    for ( ; ; ) 
    {
        application_task( );
    }
}

static void gps3_clear_app_buf ( void ) 
{
    memset( app_buf, 0, app_buf_len );
    app_buf_len = 0;
}

static err_t gps3_process ( gps3_t *ctx ) 
{
    char rx_buf[ PROCESS_BUFFER_SIZE ] = { 0 };
    int32_t rx_size = 0;
    rx_size = gps3_generic_read( ctx, rx_buf, PROCESS_BUFFER_SIZE );
    if ( rx_size > 0 ) 
    {
        int32_t buf_cnt = app_buf_len;
        if ( ( ( app_buf_len + rx_size ) > PROCESS_BUFFER_SIZE ) && ( app_buf_len > 0 ) ) 
        {
            buf_cnt = PROCESS_BUFFER_SIZE - ( ( app_buf_len + rx_size ) - PROCESS_BUFFER_SIZE );
            memmove ( app_buf, &app_buf[ PROCESS_BUFFER_SIZE - buf_cnt ], buf_cnt );
        }
        for ( int32_t rx_cnt = 0; rx_cnt < rx_size; rx_cnt++ ) 
        {
            if ( rx_buf[ rx_cnt ] ) 
            {
                app_buf[ buf_cnt++ ] = rx_buf[ rx_cnt ];
                if ( app_buf_len < PROCESS_BUFFER_SIZE )
                {
                    app_buf_len++;
                }
            }
        }
        return GPS3_OK;
    }
    return GPS3_ERROR;
}

static void gps3_parser_application ( gps3_t *ctx, char *rsp )
{
    char element_buf[ 100 ] = { 0 };
    if ( GPS3_OK == gps3_parse_gpgga( rsp, GPS3_GPGGA_LATITUDE, element_buf ) )
    {
        static uint8_t wait_for_fix_cnt = 0;
        if ( strlen( element_buf ) > 0 )
        {
            log_printf( &logger, "\r\n Latitude: %.2s degrees, %s minutes \r\n", element_buf, &element_buf[ 2 ] );
            gps3_parse_gpgga( rsp, GPS3_GPGGA_LONGITUDE, element_buf );
            log_printf( &logger, " Longitude: %.3s degrees, %s minutes \r\n", element_buf, &element_buf[ 3 ] );
            memset( element_buf, 0, sizeof( element_buf ) );
            gps3_parse_gpgga( rsp, GPS3_GPGGA_ALTITUDE, element_buf );
            log_printf( &logger, " Altitude: %s m \r\n", element_buf );
            wait_for_fix_cnt = 0;
        }
        else
        {
            if ( wait_for_fix_cnt % 5 == 0 )
            {
                log_printf( &logger, " Waiting for the position fix...\r\n\n" );
                wait_for_fix_cnt = 0;
            }
            wait_for_fix_cnt++;
        }
        gps3_clear_ring_buffers( ctx );
        gps3_clear_app_buf( );
    }
}

// ------------------------------------------------------------------------ END

Additional Support

Resources